Genetic Diversity, Population Structure, and Demographic History of Exploited Sea Urchin Populations (Tripneustes Gratilla) in the Philippines

The sea urchin Tripneustes gratilla is ecologically and economically important in the Indo-Pacific region. We use population genetic methods to investigate the population structure and historical demography of exploited populations in the Philippines. Sea urchins sampled in 6 localities in western Luzon and 4 outgroup sites were sequenced for mitochondrial cytochrome oxidase-1 gene (n = 282) and genotyped for seven microsatellite loci (n = 277). No significant genetic structure was found for either class of markers, indicating either extensive gene flow across the archipelago, or that populations have high genetic diversity and have not yet attained equilibrium between genetic drift and migration following large changes in demography. Interestingly, demographic inferences from the two types of markers were discordant. Mitochondrial lineages showed demographic expansion during the Pleistocene while microsatellite data indicated population decline. Estimates for the date of each event suggest that a Pleistocene expansion could have preceded a more recent population decline, but we also discuss other hypotheses for the discordant inferences.The high genetic diversity and broad distribution of haplotypes in populations that recently recovered from fishery collapse indicate that this species is very resilient over evolutionary timescales

The application of genetics to marine management and conservation: examples from the Indo-Pacific

Molecular tools and analyses have played pivotal roles in uncovering the processes and patterns of biodiversity in the Indian and Pacific oceans. However, integrating genetic results into management and conservation objectives has been challenging, with few examples that show practical applicability. This review aims to address some of the perceived barriers to an enhanced approach that integrates molecular data into management and conservation goals, by reviewing papers relevant to both conservation and fisheries management in the Indo-Pacific region, particularly with respect to phylogeography, connectivity, and species identification, as well as stock delineation, restoration of depleted wild stocks, mislabeled marine resources and "molecular forensics." We also highlight case studies from each of these areas that illustrate how molecular analyses are relevant to conservation and management in the Indo- Pacific, spanning a variety of vertebrate and invertebrate species. We discuss the application of genetic data to the design and evaluation of the effectiveness of marine protected area networks, stock delineation, and restoration and the usage of exclusion tests and parentage analyses for fisheries management. We conclude that there is a distinct need for increasing public awareness and ownership of genetically unique lineages and, ultimately, the increased inclusion of genetic research into management policy and conservation. Finally, we make a case for the importance of clear and effective communication for promoting public awareness, public ownership, and for achieving conservation goals within the region

Impact of Ocean Warming and Ocean Acidification on Larval Development and Calcification in the Sea Urchin Tripneustes gratilla

Background: As the oceans simultaneously warm, acidify and increase in P-CO2, prospects for marine biota are of concern. Calcifying species may find it difficult to produce their skeleton because ocean acidification decreases calcium carbonate saturation and accompanying hypercapnia suppresses metabolism. However, this may be buffered by enhanced growth and metabolism due to warming.Methodology/Principal Findings: We examined the interactive effects of near-future ocean warming and increased acidification/P-CO2 on larval development in the tropical sea urchin Tripneustes gratilla. Larvae were reared in multifactorial experiments in flow-through conditions in all combinations of three temperature and three pH/P-CO2 treatments. Experiments were placed in the setting of projected near future conditions for SE Australia, a global change hot spot. Increased acidity/P-CO2 and decreased carbonate mineral saturation significantly reduced larval growth resulting in decreased skeletal length. Increased temperature (+3 degrees C) stimulated growth, producing significantly bigger larvae across all pH/P-CO2 treatments up to a thermal threshold (+6 degrees C). Increased acidity (-0.3-0.5 pH units) and hypercapnia significantly reduced larval calcification. A +3 degrees C warming diminished the negative effects of acidification and hypercapnia on larval growth.Conclusions and Significance: This study of the effects of ocean warming and CO2 driven acidification on development and calcification of marine invertebrate larvae reared in experimental conditions from the outset of development (fertilization) shows the positive and negative effects of these stressors. In simultaneous exposure to stressors the dwarfing effects of acidification were dominant. Reduction in size of sea urchin larvae in a high P-CO2 ocean would likely impair their performance with negative consequent effects for benthic adult populations

Community-based experimental culture of sea cucumbers and siganids as tool for resource enhancement

In ARCHIV 115463 v. 1The table of contents for this item can be shared with the requester. The requester may then choose one chapter, up to 10% of the item, as per the Fair Dealing provision of the Canadian Copyright Ac

Sea urchin grow-out culture : assessment of potential for implementing community-based coastal resource management (the case in Arnedo)

In ARCHIV 115463 v.

Preparation for the establishment of marine protected area : the case in Arnedo

In ARCHIV 115463 v.